Nova Patents
US7993443B2

Multilayer effect pigment

Summary by NHIP

Multilayer Titanium Dioxide Pigment

The multilayer effect pigment comprises a transparent substrate with a titanium dioxide layer, a silicon dioxide layer, and an outermost titanium dioxide layer. Distinctive optical thicknesses range from 30 to 420 nm, with specific white variants featuring inner titanium dioxide layers of 134 to 148±12 nm and silicon dioxide layers of 49 to 117±8 nm.

Claim Score by NHIP

Read claim 1, the broadest

Abstract

A multilayer effect pigment includes a transparent substrate, a layer of high refractive index material on the substrate, and alternating layers of low refractive index and high refractive index materials on the first layer, the total number of layers being an odd number of at least three, all adjacent layers differing in refractive index by at least about 0.2 and at least one of the layers having an optical thickness which is different from all of the other layers. The resulting multilayer effect pigment is not a quarter-wave stack. The present multilayer effect pigment may be used in cosmetics or personal care products.

Term

Term ended

Expired 24 January 2024, 2.7 years ago.

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24 claims: 2 independent, 22 dependent

  1. 1
    Broadest claimClaim Score 56, average(NHIP)A multilayer effect pigment comprising:a transparent substrate having a layer of titanium dioxide thereon, said layer having an optical thickness of about 85 to 385 nm, a layer of a low refractive index material on said titanium dioxide layer and an outermost layer of a high refractive index material placed on said low refractive index material layer, said high refractive index material comprises titanium dioxide having an optical thickness of from about 45 to 420 nm and the low refractive index material is silicon dioxide having an optical thickness of about 30 to 120 nm, and wherein at least one layer has an optical thickness which is different from all of the other layers, whereby the pigment is not a quarter-wave stack.
  2. 22
    A multilayer effect pigment comprising:a transparent substrate having a layer of titanium dioxide thereon, said layer having a optical thickness of 489±12 nm;a layer of silicon dioxide on said titanium dioxide layer, said silicon dioxide layer having an optical thickness of 117±8 nm;and an outermost titanium dioxide layer placed on said silicon dioxide layer and having an optical thickness of 489±12 nm, said pigment being red.